In-situ synthesis of high thermal stability and salt resistance carbon dots for injection pressure reduction and enhanced oil recovery

Carbon dots(CDs)show great potential as a new type of oil-displacing agent for unconventional oil and gas development.However,the instability and easy aggregation epitomize the challenges that accompany the application of CDs in high temperature and high salinity(HT/HS)reservoirs.In this research,novel benzene sulfonate-modified carbon dots(BS-CDs)with remarkable thermal stability and salt resistance were fabricated through an in-situ electrochemical exfoliation method.Molecular simulation verifies that the introduction of benzene sulfonate groups substantially strengthens the electrostatic repulsion between BS-CDs,leading to outstanding dispersibility and stability even at a temperature of 100℃ and salinity of 14×10^(4) mg/L.Core flooding tests show that 0.05 wt.%BS-CDs nanofluid can significantly reduce the water injection pressure by 50.00%and enhanced oil recovery(EOR)to 68.39%under HT/HS conditions.According to the atomic force microscopy(AFM)scanning results,the adhesion force between the core(after BS-CDs treatment)and oil decreased by 11.94 times,indicating that the hydrophilicity of the core surface was increased.In addition,the distribution of the adhesion force curve is more concentrated,which means that the micro-scale wettability of the core changes from oil-wet to more homogeneous water-wet.This study provides a feasible way for the development and application of good thermal stability and salt resistance CDs in unconventional reservoir development.

Thermal effect on endurance performance of 3-dimensional RRAM crossbar array

Three-dimensional（3D） crossbar array architecture is one of the leading candidates for future ultra-high density nonvolatile memory applications. To realize the technological potential, understanding the reliability mechanisms of the3 D RRAM array has become a field of intense research. In this work, the endurance performance of the 3D 1D1 R crossbar array under the thermal effect is investigated in terms of numerical simulation. It is revealed that the endurance performance of the 3D 1D1 R array would be seriously deteriorated under thermal effects as the feature size scales down to a relatively small value. A possible method to alleviate the thermal effects is provided and verified by numerical simulation.

Thermal stability and long-acting antibacterial activity of phosphonium montmorillonites

Na-montruorillonite （Na-MMT） was exchanged with three quaternary atkylphosphonium salts： decyl tributylphosphonium bromide （DTBPBr）, dodecyl tributylphosphonium bromide （DDTBPBr） and hexadecyl tributylphosphonium bromide （HDTBPBr）, to investigate the effects of phosphonium salts species and relative molecular mass on the characteristics, morphology, thermal stability and long-acting antibacterial property of phosphonium montmorillonites. The resulting modified montmorillonites were characterized by the FTIR, XRD, TEM, and TG/DTG techniques. And minimum inhibitory concentration （MIC） was used to investigate antibacterial activity. The results show that the phosphonium salts are intercalated into Na-MMT, and the basal spacing of P-MMTs is enlarged with the increase of phosphonium salt content or the growth of alkyl chain length. DDTBP-MMT-3 with 19.83% （mass fraction of dodecyl tributylphosphonium salts, displays excellent thermal stability and long-acting antibacterial activity.

Synthesis and Solution Properties of Comb-like Acrylamide Copolymers

A comb-like acrylamide copolymer （HCJ-1） was synthesized by using aqueous free radical polymerization of acrylamide （AM） as main monomer and ether carboxylate as functional monomer. The copolymers were characterized with FT-IR and SEM. The SEM results show that the molecular structure of copolymer is extended in salt water. It is proved that the copolymer shows good salt resistance.The solution properties of HCJ-1 were studied and compared with those of partially hydrolyzed polyacrylamide （HPAM）. The experimental results show that the obtained HCJ-1, compared with HPAM, exhibits a dramatic enhancement in the salt-resistant properties. The apparent viscosity retention rate of 1.5 g/L HCJ-1 aqueous solution and salt solution after 180 days at 60 ℃ are 70.6% and 64.5%, respectively, exhibiting good thermal stability. In addition, HCJ-1 solution also displays the excellent shearing resistance. In a word, the experimental results show the HCJ-1 is a promising profiling agent for high salinity reservoir.

Resistance to Adversity of New Poplar Clones

With four poplar clones, namely 84-323 (Populus deltoides cv. ?4-323?, 84-324 (Populus deltoides cv. ?4-324?, 79-35 (Populus ?euramericana cv. ?9-35?, and I-69 (Populus deltoides cv. 慙ux?I-69/55) as a control, researches on cold, drought and salt resistance of the clones were conducted. Electrolyte permeability under a series of low temperatures, relative water loss rate of detached leaves with time series and survival rate and growth performance in salt soil were measured. The results showed that 84-323, 84-324 and 79-35 were resistant to cold as same as I-69 (CK) and more resistant to drought and salinity than I-69 (CK).

Corrosion evaluation and resistance study of alloys in chloride salts for concentrating solar power plants

Thermal energy storage(TES)systems based on molten salt are widely used in concentrating solar power(CSP)plants.The investigation of the corrosion behavior of alloy materials in molten salt is crucial for the correct selection of alloy materials and the design of TES systems.In this study,the corrosion behavior of 304,310S,316,and In625 alloys in molten chloride salts(27 mol%NaCl-22 mol%KCl-51 mol%MgCl,)was investigated.The evolution of mass loss of the alloy samples with corrosion time and temperature and the analysis of the experimental results by scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)revealed the corrosion mechanism of the alloy samples in molten chloride salts.The main factors affecting the corrosion of the alloy samples were further analyzed.It was found that the loose multi-layer corrosion was formed on the surface of the corroded alloy samples with the increase in corrosion degree.Moreover,the experimental results.showed that Mo played a positive role in improving the corrosion resistance of the alloy samples because the presence of Mo could inhibit the outward diffusion of alloying element Cr.This work enriches the molten salt corrosion database and provides a reference for the selection of alloy materials for TES systems with potential application in CSP plants.

Surface treatment to improve corrosion resistance of Al plate heat exchangers

The correlations between thermal and physical properties were studied through thermal conductivity measurements, hardness tests, salt spray tests (AASS) among the surface treatment samples named K20, K40 with thickness of 20, 40 μm respectively and raw sample named K00. In thermal conductivity measurements, there are little differences among the samples as K00, K20 and K40, they exhibit 153.39, 150.69 and 149.76 W/(m·K), respectively. According to hardness tests, K00, K20 and K40 exhibit 87.9, 259.7 and 344.8 in Vickers values. In the result of salt spray tests to examine the effects on corrosion resistance, K00, K20 and K40 exhibit the grade of 3?5, 2.0?9.8 and 10, respectively. The mutual relation of the above results was analyzed. It is found that the surface treatments do not affect the thermal conductivity of aluminum and result in the improvement of physical properties. As a result of the technology, the surface improvement of aluminum alloy specimen is achieved without thermal degradation. It validates the ability of the aluminum plate heat exchangers with surface treatment to enhance the corrosion resistance. Present work is performed as the first fundamental threshold in the process of aluminum plate heat exchangers development to check out its possibility, therefore the next step-experimental and numerical study of practical aluminum plate heat exchangers will be made.

某型直升机超短波电台结构设计

本文开展了适用于某型直升机平台的机载超短波电台结构设计,从结构总体设计、电气互联设计、散热设计、抗冲振性能设计、三防设计等角度,全方位的阐述了设备的结构设计过程,可为同类设备的结构设计提供借鉴。

海上油田开发用抗温抗盐乳液聚合物研制与性能评价

为满足海上油田开发对聚合物溶解速度、抗温和抗盐性能的要求,使用自制的高效聚合物乳化剂和热稳定剂,采用低温复合引发体系多段引发,制备了超高相对分子质量的速溶抗温抗盐型乳液聚合物,分析了制备工艺,助溶剂、功能单体和热稳定剂加量对聚合物性能的影响。结果表明,通过工艺优化可制备得到相对分子质量2200万~2400万的聚合物,尿素和硫酸钠可显著提高超高相对分子质量抗温抗盐乳液聚合物的溶解速度;聚合时添加N,N-二甲基丙烯酰胺、自制热稳定剂和2-丙烯酰胺-2-甲基丙磺酸钠,可显著提高聚合物的抗温抗盐性能。采用电镜、激光粒度仪、GPC和TGA等方法,评价了超高相对分子质量抗温抗盐型乳液聚合物的结构及性能,结果表明,制备的聚合物乳胶粒粒径分布均匀、相对分子质量分布窄和耐温性能好,在矿化度35000 mg/L、温度75℃条件下,乳液聚合物30 d的黏度保留率大于90%。研究表明,超高相对分子质量抗温抗盐型乳液聚合物具有速溶、相对分子质量高和抗温抗盐性能好的特点,可以用于海上油田驱油开发。

热障涂层对DD6单晶燃气热腐蚀及力学性能的影响

DD6单晶高温合金材料以其优异的高温服役性能,在我国多型航空发动机制造领域拥有十分广阔的应用前景。随着我国航空发动机技术的不断发展,燃烧室涡轮前服役温度不断提升,DD6单晶高温合金无法完全满足高温、高压、高转速的服役环境,急需开展DD6单晶表面热障涂层技术研究。鉴于此,本工作采用多弧离子镀技术在DD6单晶高温合金上制备了NiCoCrAlY金属粘结层(BC),然后采用电子束物理气相沉积技术制备了Y_(2)O_(3)·ZrO_(2)(YSZ)陶瓷面层,研究热障涂层对DD6单晶抗燃气热腐蚀及力学性能的影响。结果表明:在900℃条件下,燃气热腐蚀性能测试100 h后,DD6合金表面形成了厚度约100μm的腐蚀疏松结构、孔洞及横向裂纹,DD6合金抗燃气热腐蚀性能较差;BC涂层或YSZ涂层内部未出现Na、K、Ca、Cl、S等腐蚀性元素,BC涂层表面形成了均匀连续的Al_(2)O_(3)层,在其表面粘附的Na_(2)SO_(4)未出现高温分解,腐蚀介质未对BC涂层产生侵蚀;YSZ涂层柱状晶组织具有较好的应变容限,高温时柱状晶膨胀引起柱晶间隙缩小,外部的腐蚀介质无法有效渗入YSZ涂层内部,从而避免了腐蚀介质对涂层或基体的侵蚀破坏。热障涂层对DD6单晶合金980℃条件下的抗拉强度σb、屈服强度σ_(0.2)、延伸率δ和断面收缩率ψ无不良影响,断裂模式与未涂覆涂层试样一致,均呈典型的韧性断裂。在980℃、250 MPa条件下,涂覆与未涂覆涂层的DD6试样高温持久时间和延伸率δ无明显差异,呈典型的塑性变形和蠕变变形韧性断裂机制。本工作的研究结果为DD6单晶高温合金热障涂层技术的开发与工程化应用奠定了技术支撑。

三元丙烯酰胺共聚物驱油剂 PVAA 的合成及性能测试

由乙烯基吡咯烷酮（ＮＶＰ）与丙烯酰胺（ＡＭ）、丙烯酸（ＡＡ）通过反相乳液聚合法合成了三元共聚物驱油剂ＰＶＡＡ，用正交试验法确定了聚合体系主要成分的配比，并测试了共聚物水溶液的耐盐性及热稳定性．结果表明，ＰＶＡＡ的耐盐性、耐热性均好于部分水解聚丙烯酰胺．

耐温耐盐型表面活性剂及其在油田中的应用

提出两种结构的表面活性剂 ,考察了它们的耐温耐盐性能。水溶液在 2 5 0℃温度下处理72h未观察到明显的分解 ,表明它们能耐高温 ;在矿化度大于 10 0 0 0 0mg/L ,钙镁离子大于5 0 0 0mg/L的水中仍表现出良好的表面活性 ,说明它们具有优异的耐盐性能 ,且盐含量越高 ,表面活性越强 ;在盐酸中也表现出极好的表面活性 ;防垢试验表明它们是一种表面活性剂型的防垢剂。研究了它们作为苛刻条件下的地层驱油剂、油井化学吞吐剂、酸液添加剂的油田应用效果 。

基于SAP吸水膨胀橡胶的耐温耐盐性能

以反相悬浮聚合法合成P(AANa/AMPS/DMDAAC)两性共聚高吸水树脂(SAP),并引发溶胀在SAP中的丙烯酸丁酯和丙烯酸进行原位共聚合,制备疏水改性高吸水树脂。将丁腈橡胶、改性高吸水树脂、补强剂和其他助剂借助混炼机混炼均匀,在硫化成型机上高温硫化制备吸水膨胀橡胶(WSR)。研究盐溶液种类、盐溶液浓度以及环境温度对WSR的质量吸水膨胀倍率的影响,并对吸水后的WSR进行热重分析。结果表明:盐溶液中阳离子浓度越大,化合价越高,对WSR吸水性能影响越明显,吸液膨胀倍率越小;在对WSR进行一系列不同温度下的吸液性能研究时发现,WSR在120℃具有较好的吸水膨胀性能。在环境温度达到175℃时,WSR达到失水平衡。

塔河地区深层盐膏层钻井液技术

分析了塔河油田盐膏层钻进中钻井液技术的难点,并提出了相应的技术对策。针对盐膏层的特点,优选出了聚磺硅酸盐欠饱和复合盐水钻井液体系,给出了一系列工程技术措施。以S105井为例,详细介绍了该钻井液体系的现场应用情况及维护处理措施。

耐温抗高钙盐降滤失剂的合成及其性能评价

以丙烯酸(AA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、丙烯酰胺(AM)和二甲基二烯丙基氯化铵(DMDAAC)为单体,引入纳米二氧化硅(nano-SiO2)合成了钻井液降滤失剂P(AM-AMPS-AA-DMDAAC)/nano-SiO2(简称LX-2);利用FTIR和TG等方法分析了LX-2的结构及热稳定性,并考察了LX-2的降滤失性能和耐温、抗盐、抗钙性能。实验结果表明,LX-2具有良好的降滤失能力,单独以LX-2为降滤失剂时,钻井液中LX-2的含量为0.75%(w)较适宜。LX-2的耐温性能良好,其高温抗盐和高温抗钙性能明显优于其他降滤失剂。LX-2与其他处理剂的复配性能良好,复配降滤失剂可有效提高钻井液的降滤失性能、抗盐性能和耐温性能。

稠油开采用耐高温抗盐乳化降粘剂

介绍了耐高温抗盐乳化降粘剂S -5 ,该剂是一种磺酸盐型聚合物表面活性剂 ,可用于乳化降粘法开采稠油 ;评定了该降粘剂在高温处理前后的降粘效果以及该降粘剂在硬水中乳化稠油的能力 ;

木麻黄抗逆性研究进展

木麻黄(Casuarinaequisetifolia)是热带、亚热带常绿乔木,天然生长于滨海疏松沙土中,为多用途速生树种。长期生长在恶劣的沿海气候和环境中使其具有较强的抗盐、抗风、耐瘠薄、抗涝能力。木麻黄已广泛种植于我国东南沿海,主要用于防风固沙、盐碱地改良和干旱地区绿化等,在防御沿海自然灾害、改善生态环境方面发挥了巨大作用。杂交和盐碱地露地育苗等技术使木麻黄的抗寒性也得到了较大提高。本文就近年来木麻黄抗非生物胁迫的研究进行了综述,旨在为合理开发和利用木麻黄资源提供参考依据。

柔性凝胶颗粒调剖剂的室内研究

AM/AA/AMPS/钠基膨润土采用溶液聚合法合成柔性凝胶颗粒调剖剂,以吸水倍数和弹性模量为指标,对影响凝胶颗粒合成的各因素进行了室内研究。结果表明:交联剂、AM与AA的质量比、单体总量、黏土是影响聚合物弹性模量的主要因素,AM与AA的质量比、单体总量、中和度等决定着聚合物的吸水性能。柔性凝胶颗粒优化后的最优配方为:m(AM)∶m(AA)=2∶1,w(AMPS)=0.2%,w(黏土)=7.5%,w(交联剂)=0.04%,w(引发剂)=0.04%,中和度80%。该配方下,凝胶颗粒在95℃、160 000mg/L条件下可吸水17.12g/g,老化90d后,仍能吸水15.5g/g,在高温高盐环境下具有良好的稳定性。注入0.5PV的0.5%柔性凝胶颗粒+1 000mg/L聚丙烯酰胺溶液,岩心封堵率可达90%以上。经现场试验,试验井组平均日增油3.74t/d,平均降水11.7%,起到了良好的增油降水效果。

有机钛-水解聚丙烯腈钠堵剂的研究与应用

本文报道了一种耐高温抗盐的有机钛交联水解聚丙烯腈钠冻胶堵剂。该堵剂在 １５０ ℃放置１８０ 天后粘度仍高达１００ Ｐａ·ｓ。用矿化度 １ ．２ ×１０５ ｍｇ／ Ｌ 的盐水配制的堵剂，其强度与用清水配制的堵剂相差不大。该堵剂产品为粉剂，搅拌２０ —３０ 分钟即可溶解。介绍了该堵剂在油井堵水和水井调剖中的应用情况。

耐温抗盐合成聚合物驱油剂的合成与性能评价

利用 2 -丙烯酰胺基 - 2 -甲基丙磺酸和丙烯酰胺等单体合成了适用于中原油田高温高盐地层的合成聚合物驱油剂 ,研究了合成条件对共聚物性能的影响 ,评价了合成聚合物驱油剂的使用性能。室内及现场试验结果表明 :合成聚合物具有高的抗盐能力和抗高价金属离子的能力 ,具有良好的长期热稳定性能 ;其驱油效果优于生物聚合物 。